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CHEVROLET has made its new air-suspension system easily interchangeable in production line assembly with standard full-coil suspension by adopting a 4-link-type rear suspension with short and long arms. A feature of the system is the mounting of the leveling valves within the air-spring assemblies. These valves correct riding height continually at a moderate rate, regardless of whether the springs are leveling or operating in ride motion. The system provides constant frequency ride—ride comfort remains the same whether the car is occupied by the driver alone or is fully loaded.

The environment is one of the most important issues currently facing the world and the automobile industry is required to respond with eco-cars. To meet this requirement, the hybrid vehicle is one of the most optimal solutions. The hybrid system automatically stops engine idling (idling stop), or stops the engine during deceleration to recover energy. The engine stop however creates a problem concerning the vehicle's climate control system. Because the conventional climate control system incorporates a compressor driven by engine belt, there is almost no cooling performance while the engine is stopped. Until now, when a driver needed more cooling comfort the engine has been switched back on as a compromise measure. To realize cabin comfort that is consistent with fuel saving, a 2-way driven compressor has been developed that can be driven both by engine belt while the engine is running and by electric motor when the engine is stopped.

The demands for comfort and a cleaner environment have been increasing for the past years for motorcycle as well as car manufacturers. With the need to decrease the time-to-market, there is a clear drive to apply CAE-based methods in order to evaluate new designs and to propose design changes that solve any identified problems. More specifically, the demands on the comfort of the rider are not only related to ride & handling and vibration levels(1), but also to the noise levels generated by the motorcycle. This paper presents the virtual modeling of one-cylinder engine of a motorcycle that identifies the mechanism behind the generation of an annoying noise. Furthermore, different possible design changes were evaluated in order to solve the problem. A combined experimental and numerical approach was followed to achieve this. Experiments were used to identify important parameters that determine the engine behavior and thus are critical for the modeling of such an engine.

The objective of this paper is to compare the external anthropometry of 3 and 6 year old French children with the corresponding existing crash test dummies. An anthropometry study has been performed on about 70 (respectively 80) French children aged 3 years (respectively 6). More than 40 external measurements have been acquired on each subject. They include dimensions in standing and sitting positions: heights, lengths, circumferences, weight, etc. Mean, standard deviation, minimum and maximal values are given and compared with other existing international databases. From a global point of view, dimensions observed in this study appear 12% higher than in others. Dimensions are more specifically compared with corresponding crash test dummies in order to evaluate the validity of these anthropomorphic test devices.

In order to improve the fit and comfort of helmets, we developed digital head models that represent the anthropometric and morphometric variability found in the U.S. Navy. We analyzed the size and shape variation using two related approaches. First, we used Procrustes superimposition, which minimizes the distances between all landmarks of all subjects. This allowed us to visualize the variation in landmark distribution of the face and to test for statistical differences. Second, we extracted curvatures along the surface of the head. This allowed us to characterize the variation in the shape of the head. To create a series of sized digital models, we used principal component analysis (PCA) to organize the variation in both the traditional measurements as well as the locations of the 3D landmarks. Using an adaptation of multivariate accommodation modeling we identified representative individuals who characterize 95% of the variation in size and shape.

The vehicle Heating, Ventilation and Air conditioning (HVAC) system is designed to meet both the safety and thermal comfort requirements of the passengers inside the cabin. The thermal comfort requirement, however, is highly subjective and is usually met objectively by carrying out time dependent mapping of parameters like the velocity and temperature at various in-cabin locations. These target parameters are simulated for the vehicle interior for a case of hot soaking and its subsequent cool-down to test the efficacy of the AC system. Typically, AC performance is judged by air temperature at passenger locations, thermal comfort estimation along with time to reach comfortable condition for human. Simulating long transient vehicle cabin for thermal comfort evaluation is computationally expensive and involves complex cabin material modelling.

This work describes the definition and implementation of a dedicated system (hardware and software) for the quantitative evaluation of the anthropometrics and morphological parameters of the back shape. This was applied to the digital 3D analysis of subjects affected by spinal pathologies. In fact in clinical practice it is needed to have a repeatable and easy method to frequent non invasive screening of the rib system records a 3D model of the back shape standard and automated procedure. Its clinical validation is presented.

Three-dimensional (3D) whole body scanners provide an opportunity for collecting large quantities of precise point data on human forms. However, product designers will likely always need some access to traditional point-to-point dimensional measurements. These measurements can also be obtained from the 3D whole body scanner if appropriate software is developed. This project describes a validation test for a collection of software tools designed to extract traditional dimensions from 3D whole body scans. To validate the software we scanned 123 male and female subjects on a Cyberware WB4 whole body scanner. Subjects were also measured for point-to-point dimensions using traditional instruments. We compared the mean absolute differences between traditional and software measurements to interobserver error data collected in a large traditional anthropometric survey (ANSUR), and to various criteria specific to garment applications.

Today's agri-businessman is challenged to improve his efficiency to meet higher operating costs and to counter the effects of inflation. New concepts in John Deere's line of 4-wheel-drive tractors are targeted toward this goal and provide increased productivity through power increases, improved fuel economy, comfortable convenient operator environment and controls, increased hydraulic power, improved serviceability and repairability and monitoring of more critical vehicle functions.

Electrical Air Conditioning Systems for 42 V vehicles will provide many benefits in terms of Environment protection, car Architecture, cabin Comfort and overall Safety. E-A/C Systems essentially differ from conventional ones by the use of electrical compressors. First of all, they will be particularly well adapted to new powertrains, helping to make them more environmentally friendly. Accurate control and high efficiency under the most common thermal conditions will reduce the A/C impact on fuel consumption. Besides, higher sealing integrity will cut emissions of refrigerant during normal operation and maintenance. Secondly, the use of an electrically driven compressor (EDC) will suppress a belt, and will reduce the packaging constraints. This will help to design new vehicle architectures. Thirdly, the electrification of air conditioning will allow better thermal comfort. In particular, E-A/C Systems provide a good opportunity for cabin pre-conditioning.

A new compact skid steer loader has been developed. Along with productivity and cost, the design of this loader was concentrated on improving ease of operation, operator comfort and safety, and serviceability. This paper discusses how serviceability was improved over previous model Bobcats. That is; improved accessibility to regulary serviced items, reduced service parts and improved reliability.

Weight reduction and high transmission efficiency demands are getting heavier to manual transmission (MT) for vehicle driving and fuel economy performance. Also comfortable shift feeling and low gear noise level are continuously required by customer because those sensitivity performances are directly recognized by driver which can determine the transmission's merchantability. Newly developed high torque capacity MT is based on serial transmission BG6 which is adopted into a lot of customer' vehicle. This new MT is weight reduced, shift feeling and gear noise performance are highly improved that keeps strong competitiveness in the future. Concerning shift feeling, its smoothness, force balance and cross shift performance are improved and optimized. Also for low gear noise performance, it was reduced to the level which can have advantage to competitor and highly comfortable for passenger vehicle. Those improvement technologies are reported as follows.

This paper gives a report on ergonomic approaches we tried to scooters for improvements in their riding comfort. First we conducted investigations into riding postures that offer a comfortable scooter ride. That is, we picked out major items for the evaluation of scooter riding postures and investigated a correlation between those items and their physical quantities. Our investigation revealed that room for leg and arm movements played a major role in a scooter riding posture. We further found out a high correlation between the evaluation items for legroom and the knee angles and also high correlation between the evaluation items for legroom and the ankle angle. Next we report on the result of the attempt we made at improved riding comfort by equipping the scooter seat with a backrest. To check the effects of backrest, we measured the seating pressure distribution, myogenic potential, and cardiogenic potential.

The 70 Series 4WD tractors offered by John Deere has been replaced by a new 9000 product line as part of the continuous improvement process to meet customer needs and provide a product with maximum value to our customers. The new model lineup is 260, 310, 360, and 425 engine HP. All models are powered by John Deere engines with the largest 3 models using the new 10.5L and 12.5L engines. The new line of 9000 Series tractors is a styled tractor family which uses many of the 8000 Series Row Crop tractor concepts and designs. This new product line provides improved operator comfort, enhanced operator conveniences, and simplified serviceability.

A combined biodynamic and vehicle model is used to assess the vibration and performance of a human operator performing driving and other tasks. The other tasks include reaching, pointing and tracking by the driver and/or passenger. This analysis requires the coordinated use of separate and mature software programs for anthropometrics, vehicle dynamics, biodynamics, and systems analysis. The total package is called AVB-DYN, an acronym for Anthropometrics, Vehicle and Bio-DYNamics. The biodynamic component of AVB-DYN is described, and then compared with an experiment that studied human operator in-vehicle reaching performance using the U.S. Army TACOM Ride Motion Simulator.

Biomechanical data on the response of the face to localized and distributed loads are analyzed to provide performance goals for a biomechanically realistic face. Previously proposed facial injury assessment techniques and dummy modifications are reviewed with emphasis on their biomechanical realism. A modification to the Hybrid III dummy, called the GM Hybrid III Deformable Face, is described. The modification produces biomechanically realistic frontal impact response for both localized and distributed facial loads and provides for contact force determination using conventional Hybrid III instrumentation. The modification retains the anthropometric and inertial properties and the forehead impact response of the standard Hybrid III head.

The automobile body industry in Indonesia is developed by the needs of motorized means of transportation, especially for passengers cheap enough to meet the consumer's buying power. To fill these needs, modifications on commercial vehicles into passenger vehicles or provisions for passenger space on special chassis had been carried out. It can be seen that basically body construction or modification in the automobile body industry is but an extension of the automobile industry in general. At present, commercial vehicles are designed to run with higher speeds and lower fuel consumption. This situation calls for a structure design that has to meet specifications generally applied to automobiles, so as to enable it to perform equally well with the basic vehicles.

The Dutch are the tallest measured people in the world. One third of the Dutch male drivers population is not properly considered in SAE standards. The potential ‘matching-problem’ between Dutch drivers and present-day's driver workspaces is being investigated by the VIMS project team. A large amount of driver workspaces in passenger cars has been measured. The measurements have been converted to 3D CAD models to be able to evaluate them with RAMSIS. RAMSIS proved to be a helpful tool to investigate the influence of package design on the driving posture of Dutch drivers and to determine areas in the package design that may not be suitable for tall drivers.

In this paper the first results of a project, initiated in the University of Coimbra and dealing with the conjugated influence of multiple stressors in riding passengers, are presented. A field study was conducted in public transportation buses, in which the subjective response of the occupants was collected and the physical parameters related to thermal comfort, air quality, vibration and noise were acquired. More than 250 responses to a subjective inquire were collected. Besides questioning the occupants about how they felt the different stressors, the questionnaires also have a final question related to how they felt the global comfort of the vehicle, in a five-point scale. Even if it looks too far, the final goal of this project is to obtain an general comfort index that takes into account the influence of multiple stressors, thus giving to vehicle manufacturers a tool to evaluate the performance of their models and to improve the vehicle friendliness to passengers.

Studies show that the pedestrian population at high risk of injury consists of both young children and adults. The goal of this study is to gain understanding in the mechanisms that lead to injuries for children and adults. Multi-body pedestrian human models of two specific anthropometries, a 6year-old child and a 50th percentile adult male, are applied. A vehicle model is developed that consists of a detailed rigid finite element mesh, validated stiffness regions, stiff structures underlying the hood and a suspension model. Simulations are performed in a test matrix where anthropometry, impact speed and impact location are variables. Bumper impact occurs with the tibia of the 50th percentile adult male and with the thigh of the 6-year-old child. The head of a 50th percentile male impacts the lower windshield, while the 6-year-old child's head impacts the front part of the hood.